A tool for surfacing an optical surface and comprising: a rigid support having a transverse end surface; an elastically compressible interface secured to the rigid support and having a first transverse end surface, a second transverse end surface and a lateral surface extending from the periphery of the first end surface to the periphery of the second end surface, said first end surface of the interface being pressed against and covering said end surface of the rigid support; and a flexible pad that can be pressed against the optical surface and which is pressed against and at least in part covers the second end surface of the interface opposite to and in line with said end surface of the rigid support is already known, notably from Japanese Patent Application 2000-317797, from French Patent Application 2 834 662 to which American Patent Application 2005/0101235 corresponds, from French Patent Application 2 857 610 to which American Patent Application 2006/0154581 corresponds, from French Patent Application 2 918 911 to which American Patent Application 2010/0178858 corresponds, from French Patent Application 2 935 627 to which American Patent Application 2011/0136416 corresponds, from French Patent Application 2 935 628 to which American Patent Application 2011/0136415 corresponds and from French Patent Application 2 953 433 to which American Patent Application 2012/0231713 corresponds.
In order to reduce the roughness of the optical surface, the tool is brought into contact therewith while maintaining sufficient tool pressure on this surface that, through deformation of the interface, the pad adopts the shape of the optical surface.
Whilst spraying the optical surface with a fluid, it is driven in relative motion with respect to the tool so that it is completely swept by the latter.
In general, the optical surface is rotationally driven and its friction against the tool is enough to drive the latter in rotation also, an eccentricity that can be varied during the course of the operation ensuring the relative movement and sweep.
The surfacing operation requires an abrasive which may be contained in the pad or in the fluid.
During the surfacing, the elastically compressible interface makes it possible to compensate for the difference in curvature between the end surface of the support of the tool and the optical surface.